JP4381669B2 - Receiver - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a receiving apparatus for receiving a broadcast.
[0002]
[Prior art]
In broadcast reception, the status of the broadcast signal has a large effect on the reception status, especially when receiving a broadcast with a moving body such as a vehicle, appropriately responding to the status of the broadcast signal that changes momentarily according to the receiving location. There is a need to. Diversity reception is known as a technique for obtaining a good reception situation even when a broadcast signal deteriorates (see, for example, Patent Document 1). Diversity reception is a technology that uses multiple antennas at the same time for reception, and can select one or more antennas appropriately according to the state of the broadcast signal, making it more stable compared to normal reception methods. The reception state can be obtained.
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-332665
[Problems to be solved by the invention]
However, since diversity reception is a method in which a plurality of antennas and tuners are operated at the same time, there is a drawback that power consumption increases when a useless operation is performed.
[0004]
An object of the present invention is to provide a receiving apparatus that can eliminate such drawbacks and can appropriately manage an operation state.
[0005]
[Means for Solving the Problems]
The receiving device according to claim 1, wherein the receiving device receives broadcasts, and a plurality of tuners and a signal output from one of the plurality of tuners or a signal output and synthesized from at least two tuners. Among the plurality of tuners, switching means for switching the number of tuners that input an output signal to the demodulation section, detection means for detecting the reception power of the broadcast wave, and the reception power , characterized in that it comprises a reliability information indicating reliability of the included and received signal in the broadcast wave, and control means for controlling said switching means in response to.
[0006]
The receiving device according to claim 3 is a receiving device that receives broadcasts, and includes a plurality of antennas, a tuner that receives a signal received by at least one of the plurality of antennas, and the plurality of antennas. Switching means for switching the number of antennas used from the inside, detection means for detecting the reception power of the broadcast wave, the reception power, reliability information included in the broadcast wave and indicating the reliability of the received signal , And a control means for controlling the switching means according to the above.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
-First embodiment-
Hereinafter, a first embodiment of a receiving apparatus according to the present invention will be described with reference to FIGS.
[0010]
FIG. 1 is a block diagram showing the configuration of the receiving apparatus according to the first embodiment. As illustrated in FIG. 1, the receiving device 100 according to the first embodiment includes RF tuners 2A to 2C in which first to third antennas 1A to 1C and first to third antennas 1A to 1C are connected, respectively. A selection switch 3 that selects any one or a plurality of RF tuners among the RF tuners 2A to 2C, a digital demodulation unit 4 that receives an output signal of the RF tuner selected by the selection switch 3, and a digital demodulation unit 4 An error correction unit 5 that corrects an error in the output signal, a demultiplexing unit 6 that demultiplexes the output signal of the error correction unit 5, and a decoding unit 7 that decodes the digital signal output from the demultiplexing unit 6. . The decoding unit 7 includes a video decoding unit 7a, an audio decoding unit 7b, and a data decoding unit 7c that decode various data such as video data, audio data, and character data.
[0011]
The receiving apparatus 100 stores a determination unit 8 that performs a determination regarding selection of an RF tuner based on information obtained in each unit of the apparatus and information input from the outside of the apparatus, and data necessary for processing in the determination unit 8 And a memory 9 is provided. As shown in FIG. 1, the selection switch 3 is controlled according to a signal from the determination unit 8.
[0012]
Various types of information included in the broadcast wave to be received are input to the determination unit 8 from each unit of the device, and information indicating the environment of the reception device 100 is input from the outside of the reception device 100. Based on the input information, the determination unit 8 sets the reception mode of the reception device 100 to the optimum reception mode.
[0013]
Next, the operation of receiving apparatus 100 will be described. The operation of the receiving apparatus 100 is executed according to control by the determination unit 8.
[0014]
FIG. 2 is a flowchart illustrating processing in the determination unit 8 of the reception device 100. This process shows an example of selecting an appropriate reception mode (mode A, mode B, and mode C) from three types of reception modes. Mode A is a reception mode in which reception is performed using a single RF tuner (for example, RF tuner 2A), and mode B is a digital demodulation unit 4 by combining outputs of two RF tuners (for example, RF tuners 2A and 2B). It is a reception mode to input to. Mode C is a reception mode in which the output signals of the three RF tuners 2 </ b> A to 2 </ b> C are combined and input to the digital demodulation unit 4.
[0015]
In step S1 of FIG. 2, the process proceeds to step S2 after waiting for the reception signal to be input, and the state of the receiving apparatus 100 is set to mode C (step S2). In step S1, the presence / absence of a received signal is determined based on, for example, pilot signal data. Next, it is determined whether or not received signal information has been acquired (step S3). Here, the mode C set in step S2 is a reception mode in which the possibility of receiving a broadcast wave to be received is the highest. Therefore, when the received signal information cannot be acquired in mode C, it indicates that the reception target broadcast wave cannot be received in any reception mode. Therefore, if the determination in step S3 is negative, it is determined that the receiving apparatus 100 cannot receive the broadcast wave (program) to be received (step S4), and the process shown in FIG.
[0016]
If it is determined in step S3 that the received signal information has been acquired, the process proceeds to step S6. In step S6, information such as received power obtained in each part of the apparatus and information input from outside the apparatus are compared with the conditions stored in the memory 9. Next, the reception mode is set to one of modes A to C according to the comparison result in step S6. The processing in step S6 and step S7 will be further described later.
[0017]
Next, it is determined whether the process should be continued or terminated. If it is determined that the process should be terminated, the process shown in FIG. 2 is terminated, and if it is determined that the process should be continued. Proceed to step S9 (step S8). In step S9, after waiting for a predetermined time, the process returns to step S6. As described above, the processes in step S6 and step S7 are repeated almost every predetermined time.
[0018]
In the above processing in steps S6 and S7, the reception mode is set by comparing the input information with the conditions stored in the memory 9. FIG. 3 is a diagram illustrating a table stored in the memory 9. In this example, the reception mode is set based on the modulation method of the broadcast wave to be received and the reception power of the broadcast wave. When the modulation method of the broadcast wave to be received is QPSK (Quadrature Phase Shift Keying), mode B is received if the received power is −60 dBm or less, and mode A is received if the received power is −59 dBm to −30 dBm. If the power is −29 dBm or more, mode A is selected. When the modulation method of the broadcast wave to be received is 16QAM (Quadrature Amplitude Modulation), mode C is received if the received power is −60 dBm or less, and mode B is received if the received power is −59 dBm to −30 dBm. If A is −29 dBm or more, Mode A is selected. When the modulation method of the broadcast wave to be received is 64QAM (Quadrature Amplitude Modulation), mode C is received if the received power is −60 dBm or less, and mode C is received if the received power is −59 dBm to −30 dBm. If B is −29 dBm or more, Mode B is selected. As described above, in the example illustrated in FIG. 3, the reception mode switching condition is different depending on the modulation method of the broadcast wave to be received. This is because even if the reception power is the same, the reception method (reception mode) that enables good reception varies depending on the modulation method.
[0019]
Although the example shown in FIG. 3 shows the case where the reception mode is set according to the modulation method of the broadcast wave to be received and the reception power of the broadcast wave, various parameters can be used as conditions. For example, the carrier interval or guard interval of the broadcast wave to be received can be used as information included in the broadcast wave to be received. Further, an error correction code, a pilot signal, or the like added to the broadcast wave to be received can be used. Furthermore, as shown in the example of FIG. 3, the received power of the received signal of the broadcast wave to be received may be used together with these pieces of information. As such received power, a numerical value corresponding to the reception sensitivity of the signal meter may be used, or a result after digitally processing the received broadcast wave may be used. Alternatively, the reception mode may be selected based on the bit error rate obtained in the digital demodulation unit 4 instead of the reception power or together with the reception power.
[0020]
As information from the outside of the receiving apparatus 100, for example, information indicating a reception position using GPS or the like, map information, vehicle speed information using vehicle speed pulses, weather information at the time of reception, or the like can be used. For example, if it is known that the current reception location is in a tunnel based on the reception position and the map information, it is found that the reason why the current reception location cannot be received is due to radio wave shielding. For this reason, in such a case, it is possible to avoid an unreasonable operation that unnecessarily increases the number of RF tuners to be used.
[0021]
When mode A or mode B is selected as the reception mode, or when the broadcast wave to be received cannot be received, it is used to receive the broadcast wave (main channel) to be received. Another channel (sub-channel) may be received using a non-RF tuner. In this case, only the main channel is received while mode C is selected, and the subchannel is parallel to the main channel while another reception mode is selected and when the main channel cannot be received. Or received alone. There may be one or more subchannels.
[0022]
As described above, in the receiving apparatus according to the present embodiment, the reception mode is switched according to the information included in the broadcast wave to be received. Therefore, the reception mode can be appropriately selected according to the type of the broadcast wave. it can. Therefore, an increase in power consumption caused by unnecessary diversity reception can be effectively prevented. In addition, since devices and circuits that are not used for receiving the main channel can be assigned to receiving the sub-channel, the receiving device 100 can be used more effectively.
[0023]
In the above-described embodiment, the information included in the broadcast wave to be received is the modulation method, carrier interval, guard interval, and error correction code added to the broadcast wave to be received and the pilot signal. It corresponds to. However, in the receiving device according to the present invention, the information included in the broadcast wave to be received is not limited to that exemplified in the above embodiment.
[0024]
In the present embodiment, the reception position, the map information, and the like are exemplified as information indicating the environment of the receiving device, but the information indicating the environment of the receiving device is not limited to that illustrated in the above embodiment.
[0025]
In the present embodiment, the selection switch 3 is provided immediately after the RF tuner. However, the selection switch may be provided further downstream, for example, after the digital demodulation unit or after the error correction unit.
[0026]
The number of RF tuners is not limited, and an arbitrary number of RF tuners of 2 or more can be provided.
[0027]
-Second Embodiment-
FIG. 4 is a block diagram showing the configuration of the second embodiment of the receiving apparatus according to the present invention. In FIG. 4, the same elements as those in the first embodiment are denoted by the same reference numerals.
[0028]
As illustrated in FIG. 4, the receiving apparatus 200 according to the second embodiment includes a first switch antenna 11 </ b> A to 11 </ b> C, and a selection switch 13 that selects any one or more antennas among the antennas 11 </ b> A to 11 </ b> C. An RF tuner 12 that receives a reception signal from the antenna selected by the selection switch 13, a digital demodulation unit 4 that receives an output signal of the RF tuner 12, and an error correction unit that corrects an error in the output signal of the digital demodulation unit 4 5, a demultiplexing unit 6 that demultiplexes the output signal of the error correction unit 5, and a decoding unit 7 that decodes the code output from the demultiplexing unit 6. The decoding unit 7 includes a video decoding unit 7a, an audio decoding unit 7b, and a data decoding unit 7c that decode various data such as video data, audio data, and character data.
[0029]
The receiving device 200 also includes a determination unit 18 that performs a determination regarding antenna selection based on information obtained in each unit of the device, and a memory 19 that stores data necessary for processing in the determination unit 18. As shown in FIG. 4, the selection switch 13 is controlled in accordance with a signal from the determination unit 18.
[0030]
Various types of information included in the broadcast wave to be received are input to the determination unit 18 from each unit of the device, and information indicating the environment of the reception device 200 is input from the outside of the reception device 200. The determination unit 18 selects an optimal antenna based on the input information. Information included in a broadcast wave to be received obtained from each unit of the reception device 200 can be reflected in the selection of the antenna in the determination unit 18. In addition, information indicating the environment of the receiving device can be reflected in the selection of the antenna in the determination unit 18.
[0031]
Further, similarly to the first embodiment, the reception power of the received signal of the broadcast wave to be received and the digital demodulator 4 together with the information included in the broadcast wave to be received and the information indicating the environment of the receiving device. The obtained bit error rate or the like may be used.
[0032]
Examples of the information included in the broadcast wave to be received and the information indicating the environment of the receiving device include the same information as in the first embodiment.
[0033]
You may make it receive another channel (subchannel) by another receiving apparatus using the antenna which is not utilized in order to receive the said broadcast wave (main channel) used as the receiving object.
[0034]
As described above, in the receiving apparatus according to the present embodiment, the antenna to be used is switched according to the information included in the broadcast wave to be received. Therefore, it is possible to select an appropriate antenna according to the type of the broadcast wave. it can. Therefore, it is possible to prevent a plurality of antennas from being used in vain and to effectively use vacant antennas.
[0035]
In the first embodiment, a plurality of RF tuners 2A to 2C, a digital demodulator 4 that demodulates signals output from the RF tuners 2A to 2C, and a digital demodulator by combining outputs of the RF tuners 2A to 2C. 4 and a selector switch 3 for switching the state of the receiving apparatus between a state where the output of the RF tuner is input to the demodulator 4 alone, and a selector switch 3 according to information on the broadcast wave to be received. Therefore, it is possible to appropriately select a reception mode according to the type of broadcast wave, and to effectively prevent an increase in power consumption caused by unnecessary diversity reception. In addition, since devices and circuits that are not used for receiving the main channel can be assigned to receiving the subchannel, the receiving device can be used more effectively.
[0036]
In the second embodiment, the plurality of antennas 11A to 11C, the RF tuner 12 that receives a signal received by at least one of the plurality of antennas 11A to 11C, and the plurality of antennas 11A to 11C Since the selection switch 13 for switching the antenna to be used and the determination unit 18 that controls the selection switch 13 according to information on the broadcast wave to be received, the reception mode is appropriately set according to the type of the broadcast wave and the like. Therefore, an increase in power consumption due to unnecessary diversity reception can be effectively prevented. In addition, since devices and circuits that are not used for receiving the main channel can be assigned to receiving the subchannel, the receiving device can be used more effectively.
[0037]
In the first embodiment, the plurality of RF tuners 2A to 2C, the digital demodulator 4 that demodulates signals output from the plurality of RF tuners 2A to 2C, and the outputs of the plurality of RF tuners 2A to 2C are combined. The selector switch 3 that switches the state of the receiving device between the state that is input to the digital demodulator 4 and the state that the output of the RF tuner is input to the digital demodulator 4 alone, and according to the information about the environment of the receiving device And a determination unit 8 that controls the selection switch 3. Therefore, the reception mode can be appropriately selected according to the environment of the receiving apparatus, and an increase in power consumption caused by unnecessary diversity reception can be effectively prevented. . In addition, since devices and circuits that are not used for receiving the main channel can be assigned to receiving the subchannel, the receiving device can be used more effectively.
[0038]
In the second embodiment, the plurality of antennas 11A to 11C, the RF tuner 12 that receives a signal received by at least one of the plurality of antennas 11A to 11C, and the plurality of antennas 11A to 11C Since the selection switch 13 for switching the antenna to be used and the determination unit 18 that controls the selection switch 13 according to information on the environment of the receiving device, the reception mode is appropriately selected according to the environment of the receiving device. Thus, an increase in power consumption caused by unnecessary diversity reception can be effectively prevented. In addition, since devices and circuits that are not used for receiving the main channel can be assigned to receiving the subchannel, the receiving device can be used more effectively.
[0039]
Regarding the correspondence of the description of the embodiment and the claims, the RF tuners 2A to 2C are the first tuner and the second tuner, the selection switches 3 and 13 are the switching means, and the digital demodulator 4 is the demodulator. The determination units 8 and 18 correspond to control means, respectively.
[0040]
In the above description, a receiving apparatus that receives digital broadcasting has been described as an example. However, the receiving apparatus can also be applied to receiving apparatuses that receive analog broadcasting such as AM radio, FM radio, and television. Can also be mixed. In the case of analog broadcasting, as information included in a broadcast wave to be received, a sound mode such as stereo, monaural, and bilingual can be used in addition to a broadcasting method and reception power.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a receiving apparatus according to a first embodiment.
FIG. 2 is a flowchart showing processing in a determination unit.
FIG. 3 is a diagram illustrating a table stored in a memory.
FIG. 4 is a block diagram showing a configuration of a receiving apparatus according to the second embodiment.
[Explanation of symbols]
2A to 2C RF tuner (first tuner, second tuner)
3,13 Selection switch (switching means)
4 Digital demodulator (demodulator)
8, 18 Judgment unit (control means)
11A to 11C antenna

Claims (5)

In a receiving device for receiving broadcasts,
With multiple tuners,
A demodulator that demodulates a signal output from one of the plurality of tuners or a signal output from and synthesized from at least two tuners;
Switching means for switching the number of tuners for inputting a signal to be output to the demodulation unit among the plurality of tuners;
Detection means for detecting the reception power of the broadcast wave;
Control means for controlling the switching means according to the received power and reliability information included in the broadcast wave and indicating the reliability of the received signal;
A receiving apparatus comprising: The control means compares the received power and the reliability information with a table in which a condition for selecting the number of tuners is set as a combination of the received power and the reliability information, and Control
In the table, as the received power is relatively large, a relatively small number is likely to be selected, and the reliability information is relatively high in relation to other reliability information. The receiving apparatus according to claim 1, wherein a selection condition is set in which a relatively small number is easily selected. In a receiving device for receiving broadcasts,
Multiple antennas,
A tuner for receiving a signal received by at least one of the plurality of antennas;
Switching means for switching the number of antennas used from the plurality of antennas;
Detection means for detecting the reception power of the broadcast wave;
Control means for controlling the switching means according to the received power and reliability information included in the broadcast wave and indicating the reliability of the received signal;
A receiving apparatus comprising: The control means compares the received power and the reliability information with a table in which a selection condition for the number of antennas is set as a combination of the received power and the reliability information, and the switching means Control
In the table, as the received power is relatively large, a relatively small number is likely to be selected, and the reliability information is relatively high in relation to other reliability information. The receiving apparatus according to claim 3 , wherein a selection condition is set in which a relatively small number is easily selected.   The receiving apparatus according to claim 1, wherein the broadcast wave modulation method is used as the reliability information.

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